RT Journal Article
SR Electronic
T1 Gravitational collapse of Mount Etna’s southeastern flank
JF Science Advances
JO Sci Adv
FD American Association for the Advancement of Science
SP eaat9700
DO 10.1126/sciadv.aat9700
VO 4
IS 10
A1 Urlaub, Morelia
A1 Petersen, Florian
A1 Gross, Felix
A1 Bonforte, Alessandro
A1 Puglisi, Giuseppe
A1 Guglielmino, Francesco
A1 Krastel, Sebastian
A1 Lange, Dietrich
A1 Kopp, Heidrun
YR 2018
UL http://advances.sciencemag.org/content/4/10/eaat9700.abstract
AB The southeastern flank of Etna volcano slides into the Ionian Sea at rates of centimeters per year. The prevailing understanding is that pressurization of the magmatic system, and not gravitational forces, controls flank movement, although this has also been proposed. So far, it has not been possible to separate between these processes, because no data on offshore deformation were available until we conducted the first long-term seafloor displacement monitoring campaign from April 2016 until July 2017. Unprecedented seafloor geodetic data reveal a >4-cm slip along the offshore extension of a fault related to flank kinematics during one 8-day-long event in May 2017, while displacement on land peaked at ~4 cm at the coast. As deformation increases away from the magmatic system, the bulk of Mount Etna’s present continuous deformation must be driven by gravity while being further destabilized by magma dynamics. We cannot exclude flank movement to evolve into catastrophic collapse, implying that Etna’s flank movement poses a much greater hazard than previously thought. The hazard of flank collapse might be underestimated at other coastal and ocean island volcanoes, where the dynamics of submerged flanks are unknown.